1.06 polar regions

8/12/2019 1.06 Polar Regions

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Geography of Earth's Polar Regions

The polar regions are the areas that surround Earths

geographic North and South Poles. The areasurrounding the North Pole is called theArcticand

includes almost the entire Arctic Ocean and

northern areas of Europe, Asia, and North America.

The area surrounding the South Pole is called

theAntarcticand includes the continent

of Antarctica and parts of the surrounding SouthernOcean.

Arctic Circle, parallel of latitude on the surface of

the Earth at 6630 N. It marks the southern limit of

the area in which the Sun does not rise on the

winter solstice (usually December 21 or 22) or set

on the summer solstice (usually June 21 or 22).

Antarctic Circle, parallel of latitude on the surface of

the Earth at 6630 S. It marks the northern limit of the

area in which the Sun does not rise on the summer

solstice (usually June 21 or 22) or set on the winter

solstice (usually December 21 or 22).


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Arctic, large, cold area of Earth around the North Pole. The Arctic includes the Arctic

Ocean, many islands, and parts of the mainlands of North America, Asia, and Europe.

The Arctic region is particularly sensitive to global warming and other climate change,

and it has a major influence on climate and weather on the rest of the planet.

Antarctica means opposite to the Arctic, Earths northernmost region.

Antarctica, fifth largest of Earths seven continents (Africa, Antarctica, Asia, Australia,

Europe, North America, and South America). Antarctica surrounds the South Pole and is a

place of extremes. It is the southernmost, coldest, iciest, driest, windiest, most remote, and

most recently discovered continent. Nearly the entire landmass lies within the Antarctic

Circle. Air temperatures of the high inland regions fall below -80C (-110

F) in winter and

rise only to -30C (-20F) in summer. Massive ice sheets built up from snow over millions of

years cover almost all of the continent and float in huge ice shelves on coastal waters.

Antarctica's vast areas of ice on land and on sea play a major role in Earths climate and

could be strongly affected by global warming. The melting of Antarctic ice could

dramatically raise global sea level.

The higher the latitude, the more daylight. Beyond the Arctic Circle there will be a period

of time during the summer when the sun never sets, and the further you are north, the

longer this period is. When I was in the arctic on holiday (!!) in 2006, the sun rose around

the beginning of June and would not set until the end of July/beginning of August.


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Warming of the Polar Regions

The effects of climate change are not the same in all parts of the world. While Earths

average temperature has risen 0.6C (1.0F) during the 20th century, some areas of our

planet are warming faster than others. The Arctic is warming twice as fast as other parts of

the world. In Alaska (USA) average temperatures have increased 3.0C (5.4F) between 1970

and 2000. The warmer temperatures have caused other changes in the Arctic region suchas melting ice and shrinking polar bear habitat. In the opposite hemisphere, the Antarctic

Peninsula has also warmed rapidly, five times faster than the global average.

These images from NASAs ICESat satellite show the

different in ice cover in the Arctic between 1980 (top)

and 2003 (bottom).


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The Warming Arctic

In the north polar region, the climate has warmed rapidly during the past few decades.

Average temperatures in the Arctic are rising twice as fast as they are elsewhere in the

world. In Alaska (USA) temperatures have increased on average 3.0C (5.4F) between 1970

and 2000.

The Arctic is showing some of the most dramatic effects of global warming. Glaciers,including parts of Greenlands massive ice sheet, are melting rapidly.Sea ice covers less of

the Arctic Ocean each summer. Snow blankets some areas for less of the year. Thawing

permafrost releases methane, a greenhouse gas, into the atmosphere. It is also causing

damage to buildings and roads. Along the coast, thawing permafrost is causing erosion, like

in the picture at the left.

Blocks of frozen ground, known as

permafrost, break off into the ocean as the

ground thaws along coast of Canada


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The numbers and species of plants and animals are also changing. Some species are

moving further north to be where it is cooler. For example, there are more shrubs

growing in the tundra of Alaska and trees are able to grow further north. Other

species have experienced population booms or declines. There used to be 24,000

Peary caribouin northern Canada in 1961. But 1997 there were only about 1100caribou. Many could not survive because were times when food was limited. Polar

bear populations may be declining because melting sea ice limits their hunting

opportunities. Meanwhile, in Alaska, spruce bark beetles are breeding faster than ever

in the warmer climate. From 1993 to 2003 the oversized beetle population chewed up

3.4 million acres of forest trees.


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1.06 polar regions

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